High Performance Ti-Doped ZnO TFTs With AZO/TZO Heterojunction S/D Contacts

Author

Nannan Zhao ; Dedong Han ; Zhuofa Chen ; Jing Wu ; Yingying Cong ; Junchen Dong ; Feilong Zhao ; Shengdong Zhang ; Xing Zhang ; Yi Wang

Author_Institution

Inst. of Microelectron., Peking Univ., Beijing, China

Volume

11

Issue

5

fYear

2015

fDate

May-15

Firstpage

412

Lastpage

416

Abstract

In this paper, we successfully fabricated Ti-doped ZnO (TZO) thin film transistors (TFTs). Al-doped ZnO (AZO) film was adopted as source/drain (S/D) electrode, forming an AZO/TZO hetero-junction S/D contact. Meanwhile, TZO TFTs with ITO S/D electrode were also fabricated for comparison. Both AZO and ITO films were fabricated using radio frequency (RF) magnetron sputtering at room temperature (RT). Compared with ITO, device with AZO S/D electrodes exhibits higher I_on/I_off ratio of 1.9 ×10 ⁹, lower I off of 570 fA, and comparable saturation mobility (μsat) of 108.6 cm² ·V ^-1 ·S ^-1. What´s more, as channel length decreases, TFTs with AZO S/D electrodes still show good performances.

Keywords

II-VI semiconductors; aluminium; electrical contacts; semiconductor doping; semiconductor thin films; sputter etching; thin film transistors; titanium; wide band gap semiconductors; zinc compounds; AZO-TZO heterojunction S-D contacts; Al-doped ZnO film; Ti-doped ZnO TFT; ZnO:Al; ZnO:Ti; radiofrequency magnetron sputtering; saturation mobility; source-drain electrode; temperature 293 K to 298 K; thin film transistors; Electrodes; Films; Heterojunctions; Indium tin oxide; Logic gates; Thin film transistors; Zinc oxide; AZO/TZO heterojunction S/D contact; TFT; TZO; low temperature process;

fLanguage

English

Journal_Title

Display Technology, Journal of

Publisher

ieee

ISSN

1551-319X

Type

jour

DOI

10.1109/JDT.2015.2405542

Filename

7045483